
==== Front
Plast Reconstr Surg Glob Open
Plast Reconstr Surg Glob Open
GOX
Plastic and Reconstructive Surgery Global Open
2169-7574
Lippincott Williams & Wilkins Hagerstown, MD

GOX-D-24-00360
00072
10.1097/GOX.0000000000006193
3
Craniofacial/Pediatric
Original Article
Investigation of the Optimal Age in Months for Initiation of Conservative Treatment for Congenital Auricular Deformities
Takada Asuka MD *†
Kuwahara Hiroaki MD, PhD *
Tsuge Takuya MD, PhD *
Ogawa Rei MD, PhD, FACS ‡
Akaishi Satoshi MD, PhD *
From the * Department of Plastic Surgery, Nippon Medical School Musashi Kosugi Hospital, Kanagawa, Japan
† Department of Plastic Surgery, Gyotoku General Hospital, Chiba, Japan
‡ Department of Plastic, Reconstructive and Aesthetic Surgery, Nippon Medical School Hospital, Tokyo, Japan.
Asuka Takada, MD, Gyotoku General Hospital, 5525-2 Hongyotoku, Ichikawa-City, Chiba, Japan, E-mail: t2y2a2tny@gmail.com
9 2024
20 9 2024
12 9 e61931 4 2024
30 7 2024
Copyright © 2024 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of The American Society of Plastic Surgeons.
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

Background:

The effectiveness of conservative treatment for congenital auricular deformities depends primarily on the plasticity of the auricular cartilage. However, the effect remains uncertain due to various confounding factors such as differences in the characteristics of the deformity and timing of treatment initiation. In this study, we investigated the optimal timing for initiation of conservative treatment.

Methods:

We investigated the age at treatment initiation and surgical avoidance rate among 158 children with congenital auricular deformities who were treated with corrective devices at our hospital. In addition, we conducted and analyzed questionnaires containing items assessing treatment satisfaction and characteristics.

Results:

Surgical avoidance rates decreased markedly among those starting treatment after 5 months of age, and satisfaction was significantly higher in the surgical avoidance group. Multivariate analysis showed that the only factor affecting the treatment effect was the age at treatment initiation.

Conclusions:

This study suggests that the initiation of conservative treatment with corrective devices within 5 months of age for congenital auricular deformities may lead to avoidance of surgery and increased satisfaction. However, we should not judge the indication for conservative treatment solely based on age in months. Bearing in mind the effectiveness of initiating treatment within the first 5 months of age, we should initiate treatment at the earliest appropriate age with consideration of the individual patient's type and severity of deformity and cartilage elasticity.

OPEN-ACCESSTRUE
COUNTRYJAPAN
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pmcTakeaways

Question: When is the optimal timing for initiation of conservative treatment for congenital auricular deformities?

Findings: Surgical avoidance rates decreased markedly among those starting treatment after 5 months of age, and satisfaction was significantly higher in the surgical avoidance group.

Meaning: The initiation of conservative treatment with corrective devices within 5 months of age for congenital auricular deformities may lead to avoidance of surgery and increased satisfaction.

INTRODUCTION

Although the benefit of conservative treatment in the neonatal period or early infancy for congenital auricular deformity has been reported,1,2 there are very few reports assessing the appropriate age for starting treatment. According to Feijen et al,3 16 articles had been published worldwide by 2019 that refer to the initiation of conservative treatment for congenital auricular deformity, but all were limited to early infancy. To our knowledge, there are no reports comparing the effects of conservative treatment by age at treatment initiation throughout infancy (0–12 months of age). In this study, to determine the effect of the age at initiation of conservative treatment on treatment outcome, we examined the correlation between the age of treatment initiation and the surgical avoidance rate in children with congenital auricular deformities treated at our hospital.

METHODS

We analyzed 158 patients (233 ears) with congenital auricular deformities who visited the Department of Plastic Surgery, Nippon Medical School Musashikosugi Hospital and started conservative treatment between January 2019 and October 2022. For the cryptotias, helix deformities, Stahl ear, lop ears, and constricted ears, we performed treatment with splints created using a three-dimensional printer (CR-10S, Shenzhen Creality 3D Technology Company, Shenzhen, China) with elastic filaments (PolyFlex TPU95, Polymaker, Tokyo, Japan) to fit each auricular morphology. For prominent ears, we performed treatment with splints and tape. This study did not include auricular deformities with tissue hypoplasia, such as microtia. We also included only constricted ears classified as Tanzer classification group I and group II A, for which conservative treatment is considered effective.

We divided the patients into two groups; the surgical avoidance group, and the surgical indication group, based on whether they met the criteria for evaluating treatment efficacy for each disease. The criteria for evaluating treatment efficacy for each disease are as follows: for cryptotias, the auriculotemporal sulcus should be formed to the extension of the inferior crus of antihelix; for Stahl ears, the third crus of antihelix should disappear; for prominent ears, the cephaloauricular angle should be less than 30 degrees; for lop ears and constricted ears, the upper auricular drooping and prominent ear elements should disappear and the antihelix/crus of antihelix should be well formed and observable; for helix deformities and other deformities, those deformities should disappear. We defined “the surgical avoidance group” as patients whose attending physician judged that they met the above criteria. “The surgical indication group” refers to cases that have improved but still have deformities and do not meet the above criteria. In other words, “the surgical indication group” was not equivalent to cases in which surgery was actually performed. The above allocation between the two groups did not involve the wishes and opinions of the families of the patients. We also analyzed the correlation between the age in months of treatment initiation and the surgical avoidance rate. The surgical avoidance rate was defined as “the number of cases meeting the above criteria for evaluating treatment efficacy/ the total number of cases in the relevant age group in months × 100 (%).”

Age at Treatment Initiation, Surgical Avoidance Rate, and Duration of Treatment

We analyzed the age of treatment initiation, the duration of treatment, and surgical avoidance rates for the above-mentioned subjects. We also investigated the correlation between the age in months of treatment initiation and the surgical avoidance rate. Additionally, we created receiver operating characteristics (ROC) curves and calculated cut-off values.

Questionnaire Survey

We conducted a questionnaire survey of the same subjects. Survey items included treatment satisfaction (rated on a five-point scale); birth weight; number of weeks of gestation; method of delivery; comorbidities, including congenital malformations and medical conditions of the body surface; family history of congenital auricular deformity; parents’ age at birth; and birth order of the child (Table 1).

Table 1. Items of Questionnaire Survey

• What was your child’s birth weight?	
• What was the number of weeks of gestation?	
• Did you have a vaginal delivery or a cesarean section?	
• Has your child ever been diagnosed with any medical illnesses, stunted growth, or congenital anomalies of the body surface (eg, deformed limbs, mouth, eyelids)?	
  If yes, please give details.	
• Does your child have a family history of congenital auricular deformity?	
• To mother, how old were you when you had your child?	
• To father, how old were you when you had your child?	
• How satisfied are you with the treatment effects?	
 (Satisfied, somewhat satisfied, neither, somewhat dissatisfied, dissatisfied)	

First, we used Welch t test to analyze the relationship between the surgical avoidance rate and satisfaction. Second, we performed a univariate analysis between two groups: the surgical avoidance group and the surgical indication group. The analysis included the questionnaire items, gender, whether or not the patient had cryptotias, patient age in months at the start of treatment, and the duration of treatment. We analyzed continuous variables using Welch t test and qualitative variables using hypothesis testing for the difference in the population proportions. In addition, we performed a logistic regression analysis with treatment effect as the dependent variable to examine what factors impact the treatment effect. We used Mac Statistical Analysis, ver. 3.0 as our statistical analysis software and set the significance level at 5%. This study was conducted with the approval of the central ethics committee of Nippon Medical School Corporation. (ethics committee approval no.: M-2023-156)

RESULTS

Age at Treatment Initiation, Surgical Avoidance Rate, and Duration of Treatment

We studied 139 patients (211 ears), excluding 19 patients who did not return to our hospital and whose treatment course was unknown. We described the flow of this study and the distribution of patients in a flowchart (Fig. 1). We summarized patient characteristics for all cases (Table 2). The age of treatment initiation ranged from 0 months to 18 months of age. The average age of treatment initiation was 2.9 months, and the average duration of treatment was 4.5 months. There were 162 ears in the surgical avoidance group and 49 ears in the surgical indication group, of which seven ears were treated with surgery, all of which were cryptotias. We showed a photograph of one case in the surgical avoidance group (Fig. 2). This patient had a cryptotia and began treatment with a corrective device at 3 months of age. After 3 months of wear, the patient showed improvement and met the criteria for treatment efficacy and was judged to be in the surgical avoidance group. We also showed a photograph of one case in the surgical indication group (Fig. 3). This patient had a cryptotia and began treatment with a corrective device at 1 month of age, wearing it for 7 months. However, the patient did not achieve complete improvement and was judged to be in the surgical indication group. The overall surgical avoidance rate was 76.8%. The number of cases of congenital auricular deformities by disease is shown in Table 3. We counted duplicate cases with two or more deformities. Cryptotias were the most common (57 ears), followed by helix deformities (50 ears) and lop ears (44 ears). The surgical avoidance rates by deformity are summarized in Table 3. The surgical avoidance rates for lop ears and helix deformities were high at 84.1% and 84.0%, respectively, whereas those for cryptotias and constricted ears were low at 70.7% and 58.6%, respectively. We show the number of ears and the surgical avoidance rate by age in months at treatment initiation in Figure 4. Conservative treatment was initiated most frequently at 1 month of age (56 ears). We also created an ROC curve and calculated the cut-off value to be 4 months of age (Fig. 5). The surgical avoidance rate exceeded 70% for those up to 5 months of age but declined significantly for those older than 6 months of age.

Table 2. Patient Characteristics for All Cases

Sex (male)	71 (51.1%)	
Average age at treatment initiation (mo)	2.9 ± 2.51 (0–18)	
Average duration of treatment (mo)	4.5 ± 2.9 (1–16)	
Surgical avoidance rate (%)	76.8	
Surgical avoidance group (ears)	162	
Surgical indication group (ears)	49	
No. patients who underwent surgery (ears)	7	

Table 3. Surgical Avoidance Rates by Deformities

Deformity	n	Surgical Avoidance Rate (%)	
Cryptotia	57	70.7	
Helix deformity	50	84.0	
Lop ear	44	84.1	
Constricted ear	29	58.6	
Prominent ear	19	78.9	
Stahl ear	5	80.0	
Other	22	81.8	

Fig. 1. A flowchart depicting patient distribution in the study.

Fig. 2. A photograph of one case in the surgical avoidance group. A, A photograph at the beginning of treatment at 3 months of age. B, We performed treatment with a splint created using a three-dimensional printer. C, After wearing the splint for 1 month, the auriculotemporal groove began to form, but returned to its previous shape when the splint was removed. D, After wearing the splint for 3 months, the auriculotemporal sulcus was stable and there was no regression after the splint was removed.

Fig. 3. A photograph of one case in the surgical indication group. A, A photograph at the beginning of treatment at 1 month of age. B, The patient wore the splint for 1 month with no significant change. C, After 7 months of wear, the small deformity of the helix improved but the auriculotemporal sulcus did not form.

Fig. 4. The number of ears and the surgical avoidance rate by the age at treatment initiation.

Fig. 5. The ROC curve.

Questionnaire Survey

Treatment Satisfaction

We conducted a questionnaire survey of 139 patients whose treatment course was known. We presented a flowchart of the questionnaire survey (Fig. 6). In total, 68 patients (86 ears) responded to the treatment satisfaction questionnaire with a mean score of 3.82. We showed the number of ears and treatment satisfaction by age in months at treatment initiation in Figure 7. Treatment satisfaction tended to decrease with increasing age in months at treatment initiation. We also examined the relationship between treatment satisfaction and treatment effect. The number of ears for which treatment satisfaction was indicated by patients on the questionnaire was 67 in the surgical avoidance group and 19 in the surgical indication group. The mean score of treatment satisfaction was 4.0 in the surgical avoidance group and 3.5 in the surgical indication group, with significantly higher treatment satisfaction in the surgical avoidance group (Fig. 8, t (30) = 2.18, P = 0.036).

Fig. 6. A flowchart of the questionnaire survey.

Fig. 7. The number of ears and treatment satisfaction by age in months at treatment initiation.

Fig. 8. Treatment satisfaction among the surgical avoidance and surgical indication groups.

Patient Characteristics that Affect Treatment Efficacy

An estimated 75 patients responded to items other than treatment satisfaction in the survey, for a valid response rate of 54.0%. There were 55 patients in the surgical avoidance group and 20 patients in the surgical indication group.

Univariate analysis of each item between the surgical avoidance group and the surgical indication group showed significant differences in the presence of comorbidities (P = 0.005) and the age of treatment initiation (P = 0.001; Table 4). There were four cases of comorbidities in the surgical indication group, including preauricular sinus, hypohidrotic ectodermal dysplasia, and X-linked α-thalassemia/mental retardation syndrome (ATRX) syndrome, whereas there was only one case of moderate hearing loss due to exudative otitis media in the surgical avoidance group (Table 5). Multivariate analysis of comorbidities, presence of cryptotias, and the age of treatment initiation showed that the age of treatment initiation was the only factor associated with treatment effect (odds ratio 0.63, 95% confidence interval 0.48–0.84, P = 0.002; Table 6). We also generated ROC curves and calculated the area under the ROC curves (AUC) for the same three subjects. The results showed that only the age at initiation of conservative treatment was a valid indicator (Table 7).

Table 4. Comparison of Surgical Avoidance and Surgical Indication Groups by Univariate Analysis

	Surgical Avoidance Group
(n = 55)	Surgical Indication Group
(n = 20)	P	
Sex (male, n)	24 (43.6%)	11 (55%)	0.383	
Birth weight (g)	3000 ± 385	3067 ± 349	0.490	
No. weeks of gestation (wk)	38 wk 6 d ± 10 d	39 wk 2 d ± 9 d	0.310	
Method of delivery (Vaginal delivery, n)	46 (83.6%)	15 (75.0%)	0.396	
Comorbidities (yes, n)	1 (1.8%)	4 (20.0%)	0.005	
Family history (yes, n)	10 (18.2 %)	5 (25.0 %)	0.514	
Mother’s age at birth (y)	33.9 ± 4	33.5 ± 5	0.707	
Father’s age at birth (y)	36.1 ± 5	34.9 ± 6	0.457	
Birth order of the child	1.51	1.7	0.264	
Cryptotias or not (cryptotias, n)	17 (30.9 %)	9 (45 %)	0.257	
Age at treatment initiation (mo)	2.47 ± 1.7	4.95 ± 3.0	0.001	
Duration of treatment (mo)	4.31 ± 2.6	5.65 ± 4.1	0.182	
Cryptotias or not; number and percentage of patients with cryptotias in each group.

Table 5. A List of Comorbidities

	Comorbidity	No. cases	
Surgical avoidance group	Preauricular sinus	2	
Hypohidrotic ectodermal dysplasia	1	
ATRX syndrome	1	
Surgical indication group	Moderate hearing loss due to exudative otitis media	1	

Table 6. Multivariate Analysis Results

	Odds Ratio	95% Confidence Intervals	P	
Comorbidities	0.11	0.01–1.30	0.079	
Presence of cryptotias	0.59	0.17–1.98	0.390	
Age at treatment initiation	0.63	0.48–0.84	0.002	
Multivariate analysis of comorbidities, presence of cryptotias, and the age at treatment initiation showed that the age at treatment initiation was the only factor associated with treatment effect (odds ratio 0.63, 95% confidence interval 0.48–0.84, P = 0.002).

Table 7. The AUC Results

	AUC	P	
Comorbidities	0.59	0.231	
Presence of cryptotias	0.57	0.353	
Age at treatment initiation	0.76	0.001	

DISCUSSIONS

Although the frequency of congenital auricular deformity varies by ethnic group and its definitive frequency is unknown,4 plastic surgeons and pediatricians have many opportunities to treat it. Although various theories have been proposed as to the cause of congenital auricular deformity, abnormalities in the extrinsic and intrinsic muscles of the auricle are considered the most likely causes.5,6 Treatment of congenital auricular deformities can be broadly classified into conservative treatment using corrective devices and surgical treatment. In general, conservative treatment is the first choice for the treatment of congenital auricular deformities in early infancy. This is because hyaluronic acid, an important component of auricular cartilage, changes with estrogen levels and is associated with auricular cartilage plasticity.7,8 The amount of estrogen in the body during the postnatal period is highest in newborns9 and declines rapidly thereafter.10 Only 30% of congenital auricular deformities improve spontaneously.10 Therefore, the importance of conservative treatment in the early postnatal period, especially within the first week of life, with an emphasis on the plasticity of the auricular cartilage dependent on the estrogen level of the affected child, has also been reported.10,11 Many reports have shown the effectiveness of conservative treatment within the first 3 months of age,2,12 but one report has also shown corrective effects, even when conservative treatment is initiated after 1 year of age.5 To our knowledge, there are no reports comparing the effects of conservative treatment by age in months throughout infancy, and the time limit for initiation of conservative treatment remains controversial.

The results of this study showed that the surgical avoidance rate was highest in cases in which conservative treatment was initiated at 0 months of age, and the rate decreased with increasing age of the child. The cut-off value for the age of treatment initiation, calculated by the ROC curve was 4 months of age, but the surgical avoidance rate was above 70% at up to 5 months of age. In contrast, the rate was less than 40% at 6 months of age and above. In addition, treatment satisfaction tended to decrease with increasing age, and the results showed that treatment satisfaction was significantly higher in the surgical avoidance group. This suggested the effectiveness of starting conservative treatment from up to 5 months of age. However, the results of this study do not imply that initiation of therapeutic interventions after 6 months of age should be limited. As in the previous study by Yotsuyanagi et al,5 we also believe that conservative treatment should be initiated regardless of age, taking into consideration the cause of the deformity in each case, the elasticity of the cartilage, and the characteristics of the affected child. In contrast to the current situation where the timing of initiation of conservative treatment for congenital auricular deformity has customarily been left to the judgment of individual medical institutions, we believe that a higher therapeutic effect may be achieved by disseminating the usefulness of starting treatment within 5 months of age of the child to physicians and the families of affected children.

Univariate and multivariate analyses showed that only the age at treatment initiation had a significant effect on the surgical avoidance rate. In this study, the avoidance rate of surgery for cryptotias was relatively low, and in the surgical indication group, all patients who requested surgical treatment had cryptotias. For this reason, we included presence of cryptotias as one of the variables in our multivariate analysis but did not find a significant difference in the surgical avoidance rate. This may be due to the fact that, unlike other deformities, cryptotia affects not only aesthetics but also functionality with respect to the patient’s ability to wear glasses and masks, and many families of affected children thus prefer to have surgery. A report found that 82% of patients with cryptotias improved with conservative treatment, and the response to conservative treatment was the best among those with congenital auricular deformities.5 We believe that conservative treatment should be aggressively applied in cases of cryptotia. The effectiveness of the treatment of cryptotias in this study was lower than that previously reported.11 This may be due to the fact that in that previous report, even if the desired shape was not achieved for the patients and irregular forms remained, the authors judged that the ears were improved if the patients were satisfied, whereas in this study, we judged that any residual deformity was an indication for surgery, regardless of patient satisfaction.11 No significant difference was found in comorbidities. Because of the variety of types of deformities and the small number of cases, we were unable to identify any specific comorbidities that might affect the surgical avoidance rate. Among the comorbidities in the surgical indication group, hypohidrotic ectodermal dysplasia was associated with some ear diseases such as otitis media, hearing loss, and auricular deformity,13,14 and ATRX syndrome was associated with specific facial features such as auricular hypotropia.15 Both of these diseases are rare, and to our knowledge, there are no reports of treatment response to auricular deformity in these diseases. Because the auricular deformities associated with genetic abnormalities may differ from common auricular deformities in their pathogenesis and may not respond well to conservative treatment, we need to continue to investigate this issue in additional cases. Further, the present study was biased by the large number of types of auricular deformities and the relatively small number of cases in patients older than the age of 8 months at treatment initiation. Therefore, we consider it necessary to study more cases in the future.

CONCLUSIONS

In this study, the surgical avoidance rate for congenital auricular deformity was significantly higher the younger the age at which conservative treatment with corrective devices was initiated. The results also suggest that the surgical avoidance rate and satisfaction with treatment may be higher if treatment can be initiated by 5 months of age. However, physicians should not judge the indication for conservative treatment solely based on age in months at the time of medical examination. By considering the cause of the deformity and the elasticity of the cartilage in each case before selecting treatment, high patient/family satisfaction can be achieved, and surgery may be avoided in some cases.

DISCLOSURE

The authors have no financial interest to declare in relation to the content of this article.

Published online 20 September 2024.

Disclosure statements are at the end of this article, following the correspondence information.
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